Calculate the magnitude of the exact charge that is repulsed at a distance of 5 cm from

Calculate the magnitude of the exact charge that is repulsed at a distance of 5 cm from the +10 NL charge with a force of 0.9 milliNewtons.

Data: r (distance between charges) = 5 cm (in SI r = 0.05 m); q2 (known charge value) = 10 nC (10 * 10 ^ -9 C); F (repulsive force of charges) = 0.9 mN (0.9 * 10 ^ -3 N).

Reference values: k (proportionality coefficient) = 9 * 10 ^ 9 N * m2 / Cl2.

We express the magnitude of the unknown charge from the formula: F = k * q1 * q2 / r ^ 2, whence q1 = r ^ 2 * F / (k * q ^ 2).

Let’s perform the calculation: q1 = 0.05 ^ 2 * 0.9 * 10 ^ -3 / (9 * 10 ^ 9 * 10 * 10 ^ -9) = 25 * 10 ^ -9 Cl = 25 nC.

Answer: The unknown charge is 25 nC.